1. Field of the Invention
The present invention generally relates to semiconductor fabrication, and particularly to a method for fabricating handling wafer.
2. Description of Related Art
As usually known, an integrated circuit as a semiconductor device is fabricated by semiconductor fabrication processes. The integrated circuit get more complicate if the integrated circuit is more powerful, in which a large number of circuit elements with proper interconnect structure are integrated.
To fabricate the semiconductor device of the integrated circuit, the semiconductor device can be divided into two parts. A first part of the semiconductor device is fabricated beforehand separately. After then, the first part of semiconductor device is attached to a handling wafer, which serves as the actual substrate of the semiconductor device. The second part of the semiconductor device can then be fabricated on the first part over the handling wafer, according to the subsequent fabrication processes.
In the above two-stage fabrication manner, the handling wafer needs to be processed to form the protection structure on the back side and an alignment mark on the front side of the handling wafer. The front side would adapt the semiconductor device.
As can be observed, if the handling wafer is not protected well at the back side, the handling wafer would be damaged, particular to the supporting pin region. This would cause malfunction of the circuit elements at this damage area. The back side of the handling wafer need to be carefully protected to maintain the circuit function.